It is known that Gandalf disguises his voice as a troll in 'The Hobbit'. In the troll argument Gandalf would say something that Tolkien would describe as being said by "a voice". The voice seems to be stalling for time.

I suspect that in the orc argument at the footsteps of Fangorn Forest, which takes place in the Two Towers, Gandalf does this again. There is "a voice" that seems to be in favor of the hobbits.

Reread both parts and tell me what you think. Has anyone else suspected this?

If we relate speaking in an accent to this, it would take years to master talking like an orc or a troll. Gandalf probably doesn't use any powers for this, but nearly a millennia of near-solitude preparing for the war against Sauron has probably made him able to manipulate his voice in such a way.

OR all Maia have a power of speech that is understood by all beings on Middle-Earth (probably not, but the "voice" may not be explainable as to how it sounds, so Tolkien could have just left it as "a voice" as to not waste paper trying to explain what it sounds like)